MOTOR DRIVE SYSTEM FOR HYBRID VEHICLE AND METHOD FOR CONTROLLING THE SAME IN THE EVENT OF FAILURE

• US 20110133547A1
• Filed: 06/09/2010
• Published: 06/09/2011
• Est. Priority Date: 12/03/2009
• Status: Active Grant

• Current Assignee: Hyundai Motor Company (Hyundai Motor Group)
• Original Assignee: Hyundai Motor Company (Hyundai Motor Group)
• Inventors: Jang, Ki Young, Lee, Ki Jong, Joo, Jung Hong, Chun, Shin Hye, Song, Hong Seok, Park, Hyong Joon, Choi, Won Kyoung, Jung, Jin Hwan
• Granted Patent: US 8,508,067 B2
• Time in Patent Office: Days
• US Class Current: 307/9.1
• CPC Class Codes: B60L 2210/14 Boost converters
• CPC Class Codes: B60L 3/003 relating to inverters
• CPC Class Codes: B60L 3/04 Cutting off the power supply under fault conditions protective devices and circuit arrangements in general H01H; H02H
• CPC Class Codes: B60W 20/50 Control strategies for responding to system failures, e.g. for fault diagnosis, failsafe operation or limp mode
• CPC Class Codes: H02M 1/322 Means for rapidly discharging a capacitor of the converter for protecting electrical components or for preventing electrical shock
• CPC Class Codes: Y02T 10/64 Electric machine technologies in electromobility
• CPC Class Codes: Y02T 10/72 Electric energy management in electromobility

Abstract

The present invention provides a motor drive system for a hybrid vehicle and a method for controlling the same in the event of a failure in a voltage converter, in which high voltage stored in a DC-link capacitor is discharged to a 12V electrical load through a DC-DC converter, of which the output voltage is increased.

Claims

1. A motor drive system for a hybrid vehicle, the system comprising:

first and second motors for driving the vehicle;

first and second inverters for driving the first and second motors, respectively;

a DC battery for outputting a DC voltage;

a voltage converter for boosting or lowering the DC voltage from the DC battery and supplying the resulting voltage to the first and second inverters or for boosting or lowering the DC voltage from the first and second inverters and supplying the resulting voltage to the DC battery;

relay(s) connected between the DC battery and the voltage converter;

a DC-DC converter connected between the voltage converter and the first and second inverters and discharging high voltage of a DC-link capacitor, and

an electrical load driven by a 12V auxiliary battery connected to the DC-DC converter.

2. The system of claim 1, further comprising a controller for controlling the relay(s) to be turned off and controlling the DC-DC converter such that the high voltage stored in the DC-link capacitor is discharged in response to a failure detection signal in the event of a failure in the voltage converter or/and inverters.

3. A method for controlling a motor drive system for a hybrid vehicle in the event of a failure in a voltage converter, the method comprising:

turning off relay(s);

increasing output voltage of a DC-DC converter;

turning on (a) specific electrical load(s); and

allowing high voltage stored in a DC-link capacitor to be discharged to the specific electrical load through the DC-DC converter.

4. The method of claim 3, further comprising controlling, at a controller, the specific electrical load to be turned on and controlling the DC-DC converter such that the output voltage is increased if the load of the DC-DC converter is smaller than L1 as a boundary of discharge amount of the DC-link capacitor and, at the same time, if the specific electrical load is turned off.

5. The method of claim 3, wherein the specific electrical load is at least one selected from the group consisting of a water pump, an oil pump, a radiator cooling fan, a wiper deicer, an air cleaner, a high voltage battery cooling fan, a heater, a seat hot wire, headlights, an audio system, fog lamps, and taillights.

6. A method for controlling a motor drive system for a hybrid vehicle in the event of a failure in both a voltage converter and a DC-DC converter, the method comprising:

turning off relay(s);

performing switching control of first and second inverters; and

allowing high voltage stored in a DC-link capacitor to be discharged to first and second motors.

7. The method of claim 6, further comprising controlling the speed of the first and second motors driven by electrical energy discharged from the DC-link capacitor to be lower than S1 and S2 as limit values of the motor speed for discharge control.

8. A motor drive system for a hybrid vehicle, the system comprising:

first and second motors for driving the vehicle;

first and second inverters for driving the first and second motors;

a DC battery for outputting a DC voltage;

a voltage converter;

relay(s) connected between the DC battery and the voltage converter;

a DC-DC converter; and

an electrical load.

9. The motor drive system for a hybrid vehicle of claim 8, wherein the voltage converter is used for boosting or lowering the DC voltage from the DC battery and supplying the resulting voltage to the first and second inverters or for boosting or lowering the DC voltage from the first and second inverters and supplying the resulting voltage to the DC battery.

10. The motor drive system for a hybrid vehicle of claim 8, wherein the DC-DC converter is connected between the voltage converter and the first and second inverters and discharges high voltage of a DC-link capacitor.

11. The motor drive system for a hybrid vehicle of claim 8, wherein the electrical load is driven by a 12V auxiliary battery connected to the DC-DC converter.